Apparatus for removing excess wax coating from can flanges



July 29, 1952 APPARATUS FOR REMOVING EXCESS WAX COATING-FROM CAN FLANGES Filed Aug. 20, 1948 2 Sl-IEETS-SI-IEET 1 a 3 ii I a 5 m i N 00 to so I. N

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Q 9 O RalphALarson R. A. LARSON V A 2,604,871 I y 1952 R. A. LARSON 2,604,871

APPARATUS FOR REMOVING EXCESS WAX COATING FROM CAN FLANGES Filed Aug. 20, 1948 2 SHEETS--SHEET 2 gvwv/Mob RalphALarson Cldornegs Patented July 29, 952

UNITED S T S PATENT OFFICE g *APPARATUS'FORIREMOVING EXCESS WAX 1 COATING' FROM CAN FLANGES I jRalph A. iL ar sonf Chicago, Ill., assignor to Continental CanCompany, Inc., New York, N. Y.," g acorporationef New York v Application August 20, 1948, Serial No. 45,278

The following specification sets out in detail my invention in a method and apparatus for draining wax fromcan flanges. It isaddressed particularly to the production of cylindrical open-top cans for the purveying of beer and similar liquid products.

Beer and similar beverages and liquid food products are put up, customarily, in cans con taming approximately twelve fluid ounces. Such cans are entirely serviceable for this purpose, if

lined with a wax or similar coating which is not affected by the material of this type. Applying a wax coating to the interior surface of a can of this description is well-known and an example of this operation will be found fullydisclosed in the Kronquest Patent No. 2,387,273. "Briefly de scribed, the operation consists in causing the open-ended can to be passed in an inverted position over a tank of liquid wax which is sprayed from fountains into the cans. Excess wax is removed to a large extent from the interior of each can by .draining. However; it has. been found that the viscosity of the wax issuchthat a slight accumulation is localize djon the inner curved surface of the flange, This undesired or excess deposit of wax may accrue on the flange to such an extent that it will fiakeofi, into'the can during the closing operation and thereby create an unfavorable impression on the consumer who opens the can and observes the 'wax flakes in the product. Furthermore,- the {amount of wax may be great enough to interfere with double seaming and permit leakage.-

Another disadvantage of this thickened layer is that it interferes with the effective liquidtight seaming of the can end.

It has also been found that where this deposit appears, there is a possibility that squeezing during the double seaming operation will cause the wax to creep over to the outer surface of the flange of the can and it may even extend over onto the lithographic label during subsequent processing. v

The primary object of the invention is to reduce the thickness of the wax coating on the flange of an open top can to such an=extent that it will not be flaked 01f into the canduring the closing operation nor interfere with seaming the cover to the can. Incidental to this purpose there is the possibility of completely removing the wax from the curved surface of the flange.

A further object of my invention is to improve the preparation of the can for seaming by removing this excess or-interfering'deposit of wax.

A still further object of my; invention; is to produce a thoroughly uniform minimum coat- .3 Claims. (01.118-58) ing around the flange surface and remove any drops of wax which may have been localized by the manner of draining the] can after the waxing operation. I

The invention isalso addressed to materially increasing. the speed 1.,of f the above operations over that in ordinary procedures.. y i

I have also deviseda novel I and improved mechanism by which the above purposes "can be economically and expeditiously-carried out.

For purposes of example I have shown the preferred form in which myinvention may be embodied on the accompanying drawings in which Figure 1 is a side elevation, partly broken away, of the novel machine utilized in this invention for removingundesired wax from the inner surface of anend flange of a can; Figure 2 is a top plan view of the 'sarne'partly in section; i f

Figure 3 is a vertical crosssection of the improved machine taken on the line 3-3 of Figure 2;

Figure v4 is a fragmentary. longitudinal cross section of a flanged can after waxing and upending prior to my treatment and Figure 5- is a similar view of the flanged end after the undesired wax has been removed.

Briefly described, my invention consists in removing the undesired wax from the inner surface a of the end flange by reheating this portion ofthe can in upended .position and simultaneously spinning the can on its vertical longitudinal axis. By this operation the undesired part of the wax is melted and drains back into the can. This accomplishes a uniform redistribution of the wax so that the thickness and weight of the wax surface on the flange is no greater than that of the remaining interior surface." In fact, the operation may be continued until all apparent wax has been removed from the flange and the remaining surface coating is of imperceptible thickness.

Following the operation of redistribution, the flanged end of thefcan is cooled,- preferably by exposure to artificial cooling agencies. l In both the reheating 'and c ooling, steps, the can is given a'rapid rotationfas well as "travel past the heat exchange d evic'e'sothat theeffect shall be uniform around thecircumfer'enCe of the flange and the result obtained'in-the' least Possible time.

By way of exampleyI have shown the novel invention'as carried out on 'a machine. ofthe followingdescription. 2

I provide a stand 1 which may be "built up of legs 8 and 9. These legs are arranged in pairs, each of which supports a cross head Ill. The

A similar endless discharge conveyor it receives the treated cans at the opposite ends of the device.

Each cross head It supports a vertical bearing i! for a shaft 18. A pulley wheel 19 is attached to the upper end of each shaft l8. A belt 20 is trained over the wheels l9, l9 and its inner flight is arranged parallel to the side rail l4 and at a distance from it equal appoximately to the diameter of the cans 12.

One bearing I1 is extended downwardly and the shaft [8 there terminates in a miter gearing 2|. The second member of .the miter gearing is held on a horizontal cross shaft 22, as shown in Figure l.

A bracket 23 mounted upon the legs and 9 at this end of the machine supports an electric motor 24. This motor drives a speed reducer 25 which, by means of a drive belt 26, rotates the cross shaft 22.

In this way; the inner flight of the belt 28 is caused to move in the direction from the inlet to the discharge end of the machine.

The platform I I carries a series of brackets 2i, the upper ends of which support a longitudinal bar 28. This bar is located between the flights of the endless belt 20. A series of leaf springs 22 are fixed on the inner side oi the bar 28 and press against the inner flight of the belt 28. In this way, the belt is effectively held in frictional contact with the cylindrical sides of the cans.

A fuel pipe 30 is arranged to lead gaseous fuel, or a combustible mixture, to the machine for heating the open flanged ends of the cans. This fuel pipe 30 has a cut-off valve 3!.

The pipe 30 leads to a manifold 32 which has two branches 33, 33. These branches run horizontally and parallel to the platform ll. They are supported on one cross head, as shown at 34. Thebranch on the opposite side may be supported on the brackets 21 or similar devices.

A series of inwardly directed horizontal nozzles 35' is provided on each branch 33 of the manifold. This series is just beneath the horizontal plane of the flanges of the cans, as shown in Figure 3, so that small horizontal jets of flame from the nozzles will provide localized heating to the flange portions and the adjacent part of the side wall of each can.

The fuel pipe 30 is placed midway of the distance between the cross heads Hi, ill and is directed toward the incoming end of the devices.

Closely adjacentto the fuel pipe 30 is a cold air pipe 36. The pipe36 ends in a horizontal manifold 31 supported atv its opposite end on the second cross head ID. This] manifold 31 has a series of inwardly directed nozzles 38 adapted to deliver jets impinging on the flanges, as shown in Figure 1.

In Figure 4, I have shown the upended flange of an open-top cylindrical can. This view is taken at the conclusion of the waxing operation and shows the increased thickness 39 of the wax 40 which has drained down upon the curve of the flange.-

Figure 5 is a similar view of the flanged side after treatment of the can by my method and in the above described mechanism. The view graphically illustrates the extent to which the undesired wax has been caused to flow back into the interior of the can and restore a uniform thickness over the entire surface including that of the flange.

As explained above, the coating may even be attenuated by this treatment to less than the normal thickness of the can lining.

The cans are fed from the lining or waxing machine at a speed of approximately 250 per minute. A twister is used to invert the cans so that the open ends are up and feed them thus to the presently described machine. The feeding belt of this machine has a speed of from '75 to feet per minute and will thus treat up to 400 or more l2-ounce cans per minute. Due to the rapid rotation, the remelted wax will be caused to follow circumferentially of the can wall as well as axially. This will be a spiral trajectory. As a result of this, the excess wax is spread out more evenly over the cylindrical surface of the can without forming thickened streaks.

The operation of the machine is such that any drops, lumps or thickened areas on the flange will be remelted and drained'back onto the inner cylindrical wall of the can. Normally, the thickness of the coating is thus reduced at least to that of the cylindrical wall, namely, 3.5 milligrams weight of wax for the area under treatment.

The mechanism above described is effective to carry out the purposes of the invention. Thus the endless belt advances the individual cans past a line of heaters applying localized heat to the flange areas. The heating is made uniform by the belt which causes the cans to roll along the side rail. Adequate friction is maintained by the spring pressure on the belt. This is followed by passage through the cooling zcne under similar operating conditions. The great rapidity with which the operations are carried out insures correct treatment for a maximum number of cans.

The above example of the preferred form of structure illustrates the invention without, however, limiting its scope except as set out in the following claims.

I claim: I

1. An apparatusfor removing surplus hardened wax from the inner surface of a can end flange formed thereon during the coating of the interior of the can, comprising a platform on which the cans are supported with the flange uppermost and along which they are moved, a fixed guide extending along one side of the platform and disposed so that the side of the can may contact therewith, a moving belt disposed along the opposite side of the platform and contacting with the can opposite the guide for holding the can in contact with the guide for causing the can to rotate and move along said guide and platform, a row of heating elements above and parallel to the first part of the guide, and a row of cooling elements above and parallel to the second part of the guide, said heating elements and cooling elements being positioned so that they operate in succession on the flange portions of the can. i

2. An apparatus for removing surplus hardened wax from the inner surface of a can end flange formed thereon during the coating of the interior of the can, comprising a platform on which the can are supported with the flange uppermost and along which they are moved, a fixed guide extending along one side of the platform and disposed so that the side of the can may contact therewith, a moving belt disposed along the opposite side of the platform and contacting with the can opposite the guide, spring means for moving the belt inwardly toward the guide for holding the can in contact with the guide for causing the can to rotate and move along said guide and platform, a row of heating elements above and parallel to the first part of the guide and a row of cooling elements above the second part of the guide, said heating elements and cooling elements being positioned so that they operate in succession on the flange portions of the can.

3. An apparatus for removing surplus hardened wax from the inner surface of a can end flange formed thereon during the coating of the interior of the can, comprising a platform on which the cans are supported with the flange uppermost and along which they are moved, a fixed guide extending along one side of the platform and disposed so that the side of the can may contact therewith, a moving belt disposed along the opposite side of the platform and contacting with the can opposite the guide for holding the can in contact with the guide for causing the can to rotate and move along said guide and platform, a row of heating elements above and parallel to the side of the platform for heating the flange of the can as it moves along the first part of the guide, and a row of cooling elements above the guide beyond the heating elements, said heating elements and cooling elements being positioned so that they operate in succession on the flange portions of the can.

RALPH A. LARSON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 487,571 Hume Dec. 6, 1892 932,609 Hodgson Aug. 31, 1909 1,104,503 Hodgson July 21, 1914 1,705,084 Draper Mar. 12, 1929 2,021,485 Huebner Nov. 19, 1935 2,124,853 Grupe July 26, 1938 2,159,318 Carter May 23, 1939 2,197,742 Burk Apr. 16, 1940 2,257,740 Goebel et a1. Oct. 7, 1941 2,330,124 James Sept. 21, 1943 2,371,885 Gladfelter et al. Mar. 20, 1945 FOREIGN PATENTS Number Country Date 5,760 Great Britain 1905 

